Weld rod for arc welding



1,643 274 Sept 03 c. B.,LANGSTROTH ET AL WELDROD FOR ARC WELDING Fild y 25, 1923 INVENTORS:

. WG. G. Wander; .3 DEL.

MATTORNEYS.

Patented Sept. 20, 1927.

UNITED STATESOPATIENT OFFICE.

CLIFFORD B. LANGSTRO'IH AND GEORGE G. WONDER, OF MILWAUKEE, WISCONSIN, A8

SIGNORS TO A. 0. SMITH CORPORATION, OF MILWAUKEE, WISCONSIN, A CORPORA- 'I'ION OF N EW YORK.

warm non ron ARC WELDING.-

Application flled Kay 23, 1828. Serial No. 640,838.

This invention relates generally fro-the type of metallic-arc weldrod in the form of a metallic wire provided with a chemically treated combustible coating or coverin 6 which may be so formulated andconstitute as to create a non-oxidizing atmosphere about the arc during the fusion of the weldrod in the performance of the welding operation, and involves an improvement on the coated or covered weldrods disclosed in the patents to R. S. Smith,-No. 1,301,331, April 22, 1919, and No. 1,347,184, July 20, 1920.

The patent first mentioned contemplates a weldrod formed as a wire and provided with a coating or covering of paper. The atent last mentioned contemplates a wel rod formed as a wire and provided with a covering or coating of compounded paper pulp and clay formed and impacted thereon, the coating or covering in its plastic state being applied to this wire as the latter is drawn through an orifice in a stuff chest from which the compound is exuded under pressure, so as to take the form of and cover the wire. In both constructions, silicate of soda is employed as a saturant. In both,

it acts as a binder and retarder of combusw tion of the covering material.

The weldrods dlsclosed in the previous patents have been extensively used with success. But our present invention represents a development of continued experimentation, having for its purpose the production of a weldrod capable of more satisfactorily achieving the purposes and results of the patented structures, and yet susceptible of a very material reduction in its manufacturing cost. In such experimentation we have discovered that compounds having other formulae than those disclosed in the patents referred to may be used as a coatmg or covering for the mm, and permit the attainment of a more highly perfected weld- 5 ing operation, in that some objectionable conditions attendant upon the use of the atented weldrods have been remedied. he formation of gases, the expansion of which exerted a destructive tendency upon the coatin or covering, and the presence in the welde joint of refractory slags due to the employment of kaolin in the coating or coveripg, have been obviated in our new weldro In carrying out the plans of our. present nvention, we employ as a base for the coatmg or covering 0 the wire a material in the 1 form of mechanically produced wood flour or meal. This finely comminuted material is treated to remove its gas producing resinous c onst1tuent by digesting it in a stronglalkalme solutionfor a suitable period of. time, after which it is washed to free it from" the alkali and then dried to remove the molsture. The wood fibre when thus condi-' tioned 15 mixed with sodium silicate to produce a plastic mass, which may be exuded under pressure to form a tubular sleeve-likecoating or covering about the wire as the latter is drawn throu h an orifice of the stuff chest containing tfie plastic compound. After drying to expel the moisture from they covermg, the weldrods are ready for use.

The novel features of our invention will be pointed out in the appended claims. '7 In the drawing: i Flgure 1 is a view in elevation showing a weldrod formed as a metallic wire pro-' v1ded with a coating or covering, in accordance wit-h the pur oses of our invention, the weldrod being bro en out at'the center.

F1 2 1s a horizontal sectional view on the line 2'-2, Fig. 1. Fig. 3 is an enlarged view in elevation showmg a'short intermediate section of the weldrod, with the coating or covering broken away at one side. p 7 Referring to the drawing, the numeral 10 indicates a length of wire, by means of which the electric current forming the metallic arc is conducted in the welding operation, and designed to form the core of our improved weldrod. By means of the are thus formed, the wire is fused, and in order tomaintain the are as a constant during such weldlng, the wire is fed toward the work in the ratio of its fusion or consumption. It is desirable that the properties of the wire bear such relation to those of the work, that complete amalgamation of the molten -metal flowing from the current conducting wire with the fused areas of the work wil take place and a sound joint will be produced. We apply to the wire 10 a compounded 106 coating. or covering 11, while the material forming the latter is in a plastic state, one

of the purposes of such covering or coating being to create a slowly disintegrating sleeve-like envelope for the wire, so that a ering soda, the effect of the heat resisting qualities of which is to retard combustion of the tonducive to the v in the stuff chest, an upon Q improved fibrous material forming the base of the compound. We also create and surround the arc with a non-oxidizing atmosphere as roduction of a perfect weld which is free rom blemish.

In pregaring the compound for covering or coating t e wire, we use as a base, a material in the form of mechanically reduced soft wood flour or meal, which is 'gested for asuitable period of time in sodium hydroxide to remove the lignins, resins, pentosans,hexo-- sans, beta and gamma cellulose, which are some sources of the premature gasification, therefrom. The mixture is then washed to free it from the alkali and the above alkali soluble constituents, and afterwards heated to expel the moisture. By the addition of sodium silicate the lumpy mixture is formed into a astic compound of such constituency as to owfreely under pressure but not vo funtarily, so that it will cohere in any formation imparted to it. 4

The wire designed to form the core of an weldrod is passed through a stufi chest, emerging therefrom through a contracted orifice. The lastic mass is placed the application of pressure is caused to flow through the orifice with the wire. The latter emerges from the orifice at a uniform rate of speed, and the exuded lastic material is formed and impacted a ut the wire by compression so as to completely coat or cover the same. The

rinaj al purpose of the coating or covering is to orm a medium for carrymg the heat resisting and non-oxidizing elements,- and it fore described. The t ickness of the coating or covering may therefore be determined by the particular conditions attending its use. T e coated or covered weldrods when dried are ready for use. But we may 've them a final coatof sodium silicate, w ich latter may be applied either before or after the drying operation.

The coating or covering which we apply to. thewire 18 free from constituents too readily gasified, the expansion of which during the welding operation has a tendency to disintegrate the coating prior to its disintegration under heat.

' Having we claim and desire to secure by Letters Pat ent of the United States, is:

1. JA weldrod constituted as a metallic wire provided with a coating or covering of wood flour previously digestedto remove its gas producing roperties. v

2. A weldro constituted as a metallic wire provided with a coating or covering of wood flour previously digested to remove its gas producing properties and saturated with a heat resisting compound.

3. A .weldrod constituted, as a metallic wire provided with a coating or covering of wood flour previously digested to remove its gas producin properties and saturated with silicate of so a. f

4. A weldrod constituted as a metallic wire having formed and impacted thereon a coatin or covering of finely comminuted wood our, from which the gas producing properties have been removed, and having mixed therewith a heat resisting substance.

In testimony whereof, we have signed our names at Milwaukee, this 21st day of May,

CLIFFORD B. LANGSTROTH. G. G. WUNDER.

thus described our invention, what; 

